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The Case
Svobodová, Hana ; Šrek Bromová, Veronika (referee) ; Gabriel, Michal (advisor)
I assume huddled topic that I put into my past work as well as in final work. Casting my body, which is covered with feathers and create a cocoon of him, husk without the interior. Sculpture has two sides, the principle of duality, femininity and counterpart. Outer packaging evokes pleasant birdlike body surface and in the inner part aggressively squeeze ends of the wicks feathers.
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A comparative study of ultimate load and stiffness of metal-to-composite joints
Tchír, Michal ; Šebek, František (referee) ; Vrbka, Jan (advisor)
V současnosti jedna z metod spojování zejména tlustých a vysoce zatížených kompozitních komponent je šroubový spoj, který je možné rozebrat pro případ opravy na rozdíl od lepeného spoje. Kompozitní konstrukce se tradičně dimenzují tak, aby během provozu nedošlo k porušení první vrstvy laminátu, nicméně důležité je taky poznat chování laminátu po porušení první vrstvy. Pro strukturální analýzu nejenom spojů, ale také dalších komponent se používá metoda konečných prvků a protože moderní nelineání řešiče jsou schopné modelovat chování laminátu po porušení první vrstvy, tato schopnost jednoho z nich byla využita v této práci při zkoumaní chování sklolaminátu spojeného s hliníkovou částí šrouby. Konečno-prvkové modely dvou spojů kovové a kompozitní části konstrukce schopné popsat progresivní porušování laminátu byly postaveny s využitím tří různých poruchových kritérií – kritéria maximálního napětí, kritéria Hill a kritéria Tsai-Wu. Problém byl řešen s využitím řešiče Nastran. Křivky síla-posuv, tuhost-posuv a hodnoty zatížení při hraničním posuvu byly porov-nány s výsledky experimentů. Jelikož faktor zbytkové tuhosti ovlivňuje výsledky ana-lýzy progresivního porušování, byly provedeny citlivostní studie zkoumajíci vliv faktoru na přesnost a stabilitu výpočtu. Shoda výpočtu s experimentem v případe prvního šroubového spoje je méně uspokojivá, nicméně shoda v případě druhého spoje, který má zesilující tenkou ocelovou destičku na spodní straně, je podstatně lepší. Vý-borná shoda je zejména při použití interaktivních kritérií Hill a Tsai-Wu.
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Technical documentation of parts made from composite materials
Vlček, Dalibor ; Urík, Tomáš (referee) ; Klement, Josef (advisor)
This bachelor thesis describes the rules applicable for creation of technical documentation of parts made from composite materials. In the first part of this paper a brief characteristics of composite materials is introduced. In the subsequent parts the thesis deals with the basic principles of creating the documentation according to the European standard EN 4408. The main aim of this thesis is to summarize the rudimental conventions that refer to drawing of technical documentation of aircraft composite parts.
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Solving the phase of floors of an apartment house in Brno
Meluzínová, Lucie ; Čech, Josef (referee) ; Hrazdil, Václav (advisor)
Subject of this thesis is the phase of floors in apartment house in Brno. This thesis contains technical reports, statement measurement, technological specification, site equipment, scheduling, mechanical assembly design, monitoring and test plans, budgeting, safety work and environmental protection.
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History of Materials for Production of Cross-country skis
Ptáček, Ondřej ; Němec, Karel (referee) ; Molliková, Eva (advisor)
The present bachelor thesis is of a retrieval type. The first part deals with the development of cross-country skiing and the development of materials and technologies used in the production of cross-country skis from the mid-20th century to the present. It also explains important concepts in terms of design, shape and types of cross-country skis. Additionally, materials for cross-country ski poles are outlined and their differences are discussed. The second part refers to some of the materials used in the manufacture of cross-country skis, or cross-country ski poles. The emphasis is mainly laid on composite materials and matrices. The matrix in composites is reinforced using fibre or other type of filler.
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The Visual Style of Canoe Races in Týn nad Vltavou
Šafářová, Gabriela ; Marešová, Věra (referee) ; Macháček, Mikuláš (advisor)
I focused on design of information and promotional materials of Canoe Marathon World in Tyn nad Vltavou. I concentrated mainly on the failures of the current visual style and proposed new solutions. The key is to design a new logo and its modifications, which will be put to use in a slight variation in the coming years. Art themes based on specific objects, materials and phenomena (lamina structure, paddles, movement) are simplified into almost abstract forms.
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Assessment of fracture risk for a langlauf ski made as a glass fibre reinforced sandwich
Láštic, Daniel ; Majer, Zdeněk (referee) ; Burša, Jiří (advisor)
The first part of bachelor’s thesis is devoted to basic theoretical knowledge about usage of sandwich theory of beams, which are made of different materials in the core and faces. This part includes brief description of composites (common car- rying component of sandwich structures) with emphasis put on the fibre compo- sites and laminates. A special characteristic of composites – orthotropy is men- tioned. The second part is focused on description of obtaining of elastic constants of materials used in the real cross-country ski by experiment, on stress calculation and fracture risk assessment in cross-country ski made as sandwich structure for the most adverse operational state. The solution is executed with the help of an- alytical formulas of mechanics of materials derived in this part. The problem is also solved using finite element method (FEM) employing ANSYS software.
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Propagation of inclined cracks to the interface of ceramic laminates
Novotná, Lenka ; Trunec, Martin (referee) ; Chlup, Zdeněk (advisor)
Composite materials with laminated structure provide advantages which are utilised during component design. Low density, temperature and chemical stability are the profitable properties predetermining application of ceramic laminates. The main obstacle for wide spread of ceramic materials is their inherent brittleness. Therefore, in this thesis, the crack propagation in ceramics laminates has been extensively studied. Laminated structures with various volume fractions of components (alumina and zirconia) were prepared by electrophoretic deposition. Evaluation of crack propagation through the interface and determination of basic mechanical properties was conducted on the basis of extensive literature search. Crack deflection originated in both presence of internal stresses and differences in elastic modulus during the crack interface passing was monitored. A special type of specimen geometry was employed with the aim to set arbitrary angle between crack and interface. It was experimentally found that the degree of crack deflection is dependent on entering angle and volume fraction of components. Higher crack deflection was already found in the bulk of the test piece comparing to the test piece surface. The 3D fracture surface reconstruction generated using laser confocal microscopy was used in this detailed crack propagation study. Further basic elastic and strength characteristics of laminates were determined and compared to those obtained from monolithic materials. The validity of the mix rule for elastic characteristics was confirmed by comparing of elastics modulus. The most reliable method for elastic modulus determination was marked the dynamic resonance method due to low scatter and consistency in measurement. The flexural strength of all laminates tends to be close to the flexural strength of the weakest component. Therefore the mix rule is not applicable for flexural strength estimation on the contrary of elastic characteristics. The change of component volume fraction leads only to change of flexural strength scatter. Thanks to gained knowledge about crack propagation and basic characteristic determination will be possible to design ceramic laminates more efficiently for given needs of application.
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Methodology design of ultrasound testing of composite propellers
Horňák, Pavel ; Černoch, Jakub (referee) ; Katrňák, Tomáš (advisor)
Non-destructive testing is a big concept in the field of aerospace composites. In particular, the ultrasonic defectoscopy method, the application of which to laminate aircraft propellers is the main interest of this paper. The introductory chapters introduce the propellers and the material used for their manufacturing. The focus is then on the process of manufacturing laminate propellers from carbon and glass fibre. From a selection of non-destructive methods, a recommended methodology relying mainly on ultrasonic defectoscopy is compiled. The selected Dolphicam 2+ device is described with its features and its settings calibrated on a manufactured test specimen containing predefined artificial structure defects. The evaluation shows a significant improvement in the visibility of individual defects located at different depths by using the calibrated setup. The improvement is quantified by the amplitude gain of the received signal compared to the signal captured using the default setting. The resulting output are specific recommendations for both setup changes and propeller ultrasonic testing methodologies along with real-world application. The work thus serves as a template for ultrasonic defectoscopy of laminate propellers not only for the device mentioned.
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